Electrical contact device



Feb. 2, 1965 w. HOLZER 3,168,634

ELECTRICAL. CONTACT DEVICE Filed June 25, 1962 Fig.1.

INVENTORI WALTER HOLZER YWWIWM Attorneys ing of the contact directly on the contact United States Patent Ofiice 3,168,634 ELECTRICAL CONTACT DEVICE WalterHolzer, Drosteweg 19, .Meersburg' (Bodensee), Baden, Germany Filed June 25, 1962, Ser. No. 204,950

Claims priority, application Germany, June 27, 1961,

4 Claims. (Cl. 200-466) The invention relates. to an electric contact member comprising a connector portion, a resilient intermediate portion and a contact making portion, the member being stamped in one piece and being edgewise upstanding bedisadvantagethat it requiresa considerable amount of time and material to be made insofar that the incisions have to be stamped out. When employing high currents, the considerably reduced cross sectional area 1s also a a disadvantage. Further, the construction is disadvantageous insofar that the spring constant cannot be extensively varied.

The invention aims to avoid these disadvantages and to construct the resilient intermediate portion in such a way that, without weakening the cross section, resilience is obtained in two perpendicular planes.

According to the invention, the resilient intermediate portion is formed by a connecting piece which is turned through substantially 90 between the connector portion and the contact making portion. According to this construction, the generally ed'gewise upstanding stamping is twisted through substantially 90 at selected places. This twisted length of the stamping is considerably resilient compared with the adjoining edgewise upstanding portions. The amount of resilience depends on the length of the twisted portion.

The actual twisting is readily brought about during manufacture and the resilience is sutficien-t not only to ensure the springiness at the contact making portion but also the springiness required for mounting the connector portion in openings in the two plates.

In one construction, the contact member is in the form of a stamping mounted edgewise upstanding between the plates and, adjoining the end of the connector portion, it is twisted through 90', the contact being mounted at the end of the twisted part.

This results in the formation of the contact making portion as well as the resilient intermediate portion. Mountportion is readily possible and the contact itself is resilient so that, as it is flexed when making contact, sliding friction takes place on the counter contact.

In cases where there are a plurality of juxtaposed edgewise upstanding contact members, it is desirable that the 90 twisted portions be offset from one another.

Whilst this construction involves a variation in the clamping length from the connector portion to the contact making portion, this is a negligible disadvantage compared with the resultant advantageous saving in space if the reciprocal movement of the edgewise upstanding portions is actuated by a cam disc.

It is also possible to form the stamping with alternate portions which are twisted through 90 to one another.

By means of such constructions, the contact member can be. given any desired spring constant. In addition,

. through the apertures 3, 4

The finger 5 is reciprocated in the direction of the arrow little space is available for resilience is obtained in perpendicularly lined planes because the spring force is always largest at that. place where the bending edge has the smallest height.

It is further possible to make the 90 twisted connecting pieces with a reduced cross sectional area, for example by means of forging, stamping and the like.

Such a reduction in cross sectional area corresponds to cold working and has no material influence on the current conducting area but does atfect the resilience.

Examples of the invention are illustrated in the accompanying diagrammatic drawing, wherein:

FIG. 1 illustrates an electric contact member mounted between two plates;

FIG. 2 shows a modification of the contact making portion of the contact member, and

twisted at the end of the connector trout adjacent the contact making portion.

In FIG. 1', the contact member comprising a fiat elongated resilient bar 14 is mounted between the plates 1, 2 and has finger projections 8 andS projecting respectively therein by sliding it into place.

6 by a cam 19 which turns in the direction. of the arrow 20. Two projections 7 serve a retaining means for the contact member after the connector portion 8 has been inserted. The contact 10 which bears on the counter contact 21 is fixed at the front of the contact making portion 9. The resilient intermediate portion 11 comprises a connecting piece 12 which has been twisted through This connecting piece is direction of the arrow 13. Such resilience is important for making contact between the contact 10 and the counter contact 21. Conversely, the edgewise upstanding portion 14 is strongly resilient in the direction of the arrow 15, i.e. the resilience in the direction of the arrow 13 is perpendicular to the resilience in the direction of the arrow 15.

In FIG. 2, like numerals designate equivalent parts.

The edgewise upstanding portion 14 is pretensi-oned to lie against the plate 2. Such pretension is produced by the spring whose clamping portion 16 is determined by the start of the 90 twisted connecting piece 12.

In FIG. 3, the contact 10 co-operates with a counter contact 17, In this case, two intermediate pieces 12, 18 are provided both of which are twisted through 90 relatively to the edgewise upstanding portion 14. It will be evident that this permits resilience to be obtained by simple means and at any desired place without using any special materials. By altering the cross section of the intermediate pieces 12, 18 or any other such intermediate pieces that may be present, the spring constant can be varied still further.

The invention can be employed wherever simple edgewise upstanding contact members are to have'a certain constant spring effect at selected places.

A further application is the case of housings wherein V the contacts. The intermediate wall-s between individual contacts or projections of the housings can be constructed so that they also form guides for the contacts because either the broad surfaces or the surfaces lying perpendicular thereto torm abutments therefore. The contact is not likely to stick against the. intermediate walls but will, instead, align itself resiliently. Likewise, it is important that the breadth of juxtaposed contacts need be separated by intermediate walls and, for example, only short portions, i.e. the intermediate walls can be limited to minimum sizes. In that case, the intermediate walls would be located between the strongly resilient in the' two adjacent portions each of which are twisted through 45 Of course it is not necessary that the twisting be through exactly 90 as long as the desired spring effect is obtained in the desired plane.

I claim:

1. In combination a cont-act member and means for operating said contact member, said contact member comprising a thin flat resilient bar having one end 'por-' tion anchored in fixed position and the other end portion carrying a contact, the intermediate and contact portions of the bar being movable edgewise in the plane of the side edges of the bar, the portion of the bar adjacent the anchored end having spaced alternate 90 twists defining therebetween a spring-like bendable portion having its edgewise flat surface at right angles to the edgewise flat surface of the intermediate portion, and rotary cam means tion of said bar and in the edgewise plane ofgsaid intermediate portion, and said intermediate portion having an intergr-al edgewise extending finger projecting through said aperture and contacting said rotary cam means.

4. An electrical contact bar comprising av flat resilient strip having the end portions thereof and an intermediate portion lying in a common edgewise plane, one end having spaced projections in said plane and the other end having electrical contact means, said bar having spaced twists adjacent said one end, that portion of the bar between said twists having its edgewise plane at right angles to said first edgewise plane, and said intermediate portion having an integral finger projectionextending in a direction opposite that of said first named projections and lying in the first-named plane whereby cam means operating against said projection may cause the bar to flex between said twists;

References Cited by the Examiner UNITED STATES PATENTS.

2,434,740 1/48 Glaser et al 267- 10 2,438,186 3/48 Randall ZOO- 116 2,483,939 10/ 49 Schickler 200137 2,660,646 11/53 Fritzinger 200137 BERNARD A. GILHEANY, Primary Examiner. 

1. IN COMBINATION A CONTACT MEMBER AND MEANS FOR OPERATING SAID CONTACT MEMBER, SAID CONTACT MEMBER COMPRISING A THIN FLAT RESILIENT BAR HAVING ONE END PORTION ANCHORED IN FIXED POSITION AND THE OTHER END PORTION CARRYING A CONTACT, THE INTERMEDIATE AND CONTACT PORTIONS OF THE BAR BEING MOVABLE EDGEWISE IN THE PLANE OF THE SIDE EDGES OF THE BAR, THE PORTION OF THE BAR ADJACENT THE LINE ANCHORED END HAVING SPACED ALTERNATE 90* TWISTS DEFINING THEREBETWEEN A SPRING-LIKE BENDABLE PORTION HAVING ITS EDGEWISE FLAT SURFACE AT RIGHT ANGLES TO THE EDGEWISE FLAT SURFACE OF THE INTERMEDIATE PORTION, AND ROTARY CAM MEANS ACTING UPON THE INTERMEDIATE PORTION TO MOVE THE SAID MOVABLE PORTION IN SAID PLANE ABOUT SAID BENDABLE PORTION. 